1. Field of the Invention
The present invention relates to an electrical connection box, a positioning method and a testing device for the same.
2. Description of the Related Art
A complicated electrical wiring system, such as a wiring harness, may be used with relay boxes, fuse boxes and/or electrical connection boxes. The prior art boxes include casings that have integral or unitarily formed connector portions. Connection circuits that have a multi-layer construction are in the casing and are used to collect and arrange relays, blade type fuses, and/or connectors of the electrical wiring system in one location.
For example, a prior art relay box is formed from resin and has a connector mount portion for a connector of a wiring harness. A fuse connecting portion to be connected with a blade type fuse and a relay connecting portion to be connected with a relay also may be formed on the prior art relay box to conform to the requirements of the wiring harness to be produced. The relay box is assembled into its final mode by connecting the connector with the connector mount portion and the blade type fuse with the fuse connecting portion.
The wiring harness production process includes an electrical conduction test for testing the wiring and the connection. A test for checking whether the connector is present and whether or not the connector is properly connected also are made to assure quality. If a relay box is connected, an electrical conduction test for the relay box is made.
The aforementioned prior art electrical connection box has a multitude of blocks, including the connector mount portion, the fuse connecting portion and the relay connecting portion that are integrated in a complicated layout. As a result, connection parts mounted in the individual blocks cannot be positioned easily with respect to testing parts (e.g. probe pins) for testing the connection parts. This results in poor operability and makes testing errors likely.
Moreover, a corresponding number of testing units need to be prepared for connection parts (terminals of connectors, etc.) to be mounted in the individual connecting portions. Thus, the respective testing units cannot be integrated because the maintenance of the individual testing units is, otherwise, too cumbersome.
As a result, the respective testing units are separated and the electrical conduction test for the electrical connection box is made in each testing unit. This requires time and labor for the testing.
The present invention was developed in view of the above problems, and an object thereof is to provide an integral electrical connection box which can be positioned easily and precisely, and a positioning method and a testing device for such an electrical connection box, wherein the testing device can particularly be easily maintained.
According to the invention, there is provided a method for positioning an electrical connection box with respect to a testing device when the electrical connection box is tested. The electrical connection box has blocks accommodating connection parts that are integrated in a box. The method is characterized by engaging the connection parts of the electrical connection box with probes of the testing device after restraining the box from twisting by a restraining or correcting member. Accordingly, the orientation of the box and a strain thereof during the molding can be corrected in a specified manner by the correcting member. As a result, the connection parts of the electrical connection box can be engaged with the probes easily and precisely.
According to the invention, there is further provided a device for testing an electrical connection box in which blocks accommodating connection parts are integrated in a box. The testing device comprises one or more probes for testing the connection parts of the blocks. At least one retainer is provided for retaining the probes, and at least one restraining or correcting member provided on the retainer for restraining the box from twisting. Accordingly, the orientation of the box and a strain thereof during the molding can be corrected in a specified manner by the correcting member. As a result, the connection parts of the electrical connection box can be engaged easily and precisely with the probes.
Preferably, the correcting member comprises three rods insertable through the box. Accordingly, since the rods are inserted through the box to correct the orientation of the box, the correction can be securely made by a very simple construction.
According to the invention, there is further provided a testing device for testing an electrical connection box in which blocks accommodating connection parts are integrated in a box. The testing device comprises, one or more probes for testing the connection parts of the blocks, one or more holders provided at least one for each block for holding the corresponding probes, and a retainer for individually detachably retaining the respective holders such that the probes are arranged in a layout corresponding to the blocks. Accordingly, since the probes corresponding to the blocks accommodating the connection parts are retained by the retainer via the holders when the connection parts of the electrical connection box are tested, the holders can be mounted detachably on the retainer. As a result, maintenance can be made individually for the respective probes by mounting and detaching the holder on and from the retainer for each probe, and the testing device capable of testing a plurality of connection parts at once can be constructed.
Preferably, each holder comprises at least one fixed portion to be fixed to the retainer, at least one movable portion displaceable with respect to the fixed portion, and at least one coupling portion for elastically coupling the fixed portion with the movable portion. The probe is provided on the movable portion. Accordingly, the fixed portion to be fixed to the retainer and the movable portion displaceable with respect to the fixed portion are elastically coupled by the coupling portion to make the holder detachably mountable on the retainer. Accordingly, the movable portion can hold the probe while being elastically displaceable. As a result, the probes can elastically take up displacements and dimensional variations when being connected with the connection parts of the electrical connection box.
Further preferably, each holder is formed with an opening portion for opening connecting portions of the lead wires of the probes. Accordingly, the connection of the lead wires of the probes and the mounting of armoring parts on the lead wires can be performed through the opening portion.
Preferably, the coupling portion is a coil spring into which the lead wires are introduced. Accordingly, the lead wires of the probes are free from entanglement and loosening since they are introduced into the coil spring.
According to a further preferred embodiment, there is provided a device for testing an electrical connection box in which blocks accommodating connection parts are integrated in a box. The device comprises probes for testing the connection parts of the blocks. Holders are provided, one for each block, for holding the corresponding probes. A retainer is provided for retaining the respective holders such that the probes are arranged in a layout corresponding to the blocks. Each holder comprises a fixed portion to be fixed to the retainer, a movable portion displaceable with respect to the fixed portion and having the corresponding probe mounted thereon, and a coupling portion for elastically coupling the fixed portion with the movable portion. The coupling portion preferably urges or biases the movable and fixed portions away from each other.
Accordingly, since each holder comprises the fixed portion to be fixed to the retainer, the movable portion displaceable with respect to the fixed portion and having the corresponding probe mounted thereon, and the coupling portion for elastically coupling or connecting the fixed portion with the movable portion, the movable portion can elastically and displaceably hold the probe. As a result, the probes can elastically take up displacements when being connected with the connection parts of the electrical connection box.
Preferably, the movable portion of each holder holds a plurality of probes such that the probes are individually relatively displaceable. Accordingly, the probes are individually displaceably held when the plurality of probes are mounted on the movable portion in accordance with the arrangement of the connection parts. Therefore, displacements can be taken up more minutely.
More preferably, each movable portion further comprises at least one guide projection for guiding the probe to the corresponding connection part by being brought into sliding contact with an outer wall of the corresponding block. Accordingly, since the block and the movable portion are positioned by the guide projection, the probes and the connection parts can be more easily and precisely positioned.
Further preferably, there are provided one or more checking projections which are provided integrally with the probes held by the movable portion to check whether locking portions satisfactorily lock the corresponding connection parts. Each coupling portion couples the corresponding movable portion such that the movable portion can be retracted with respect to the retainer in a direction opposite from the locking portion when the corresponding checking projection is in contact with the locking portion experiencing a locking error. Accordingly, the locking state of the locking portion for the connection part can also be checked when the connection part is tested by the probe.
Most preferably, the movable portion and/or the holders are retained or retainable in the block with a clearance or play so as to be slightly movable in a lateral direction thereof and/or to be slightly rotatable along a longitudinal axis thereof.
According to the invention, there is still further provided an electrical connection box, comprising a plurality of blocks accommodating connection parts, a box in which the respective blocks are integrated in a predetermined layout, and at least one hollow portion formed in the box for permitting a correcting member for correcting the twist of the box to be inserted therethrough. Accordingly, the strain and orientation of the box can be properly corrected during the testing by inserting the correcting member of the testing device through the hollow portion.
These and other objects, features and advantages of the present invention will become more apparent upon a reading of the following detailed description and accompanying drawings.